耙吸式挖泥船高压冲水装置的数值模拟及水力优化

Numerical simulation and hydraulic optimization of high pressure flushing device of trailing suction hopper dredger

耙吸式挖泥船可利用耙头上的高压冲水装置有效提高疏浚作业的工作效率,现有高压冲水装置管路的设计仍不完善,一些结构亟待优化。采用数值方法对某高压冲水装置进行三维建模、模拟计算和分析,发现耙头内的高压冲水管路中存在较多漩涡流,水力损失较大,导致耙头施工时达不到理想的出口总压,影响效率;针对这些问题,通过使用渐变管、圆倒角等方式改善管内流动。结果表明,优化后的耙头高压冲水管路阻力损失减少,射流水速更高,冲水总流量提高约3%,出口总压增大,破土能力提升,从而提高疏浚作业的效率。

The high-pressure flushing device on the drag head of trailing suction hopper dredger can be used to effectively improve the efficiency of dredging operation.The pipeline design of the high-pressure flushing device is still imperfect, and some structures need to be optimized. We carry out three dimensional modeling, simulation calculation and result analysis of a high-pressure flushing device by using numerical method,find that there is vortex flow near the inlet and outlet of the high-pressure flushing branch pipe in the drag head,and the hydraulic loss is large,which leads to the failure of the ideal outlet total pressure during the construction of the drag head and affects the efficiency. In view of these problems, we improve the flow in the pipe by using gradient pipe and circular chamfer.The results show that after optimization,the resistance loss of the high-pressure flushing pipeline of the drag head is reduced,the jet water speed is higher,the total flow of flushing water is increased by about 3%,the outlet total pressure is increased,and the soil breaking capacity is improved,so as to improve the efficiency of dredging operation.